Fur and Vengeance
by Fessran
Summary: No Pinecest- When Mabel finds a strange vial in the forest surrounding the Shack, she gives some to Dipper while he sleeps. Unbeknownst to her, the potion has some very odd side affects... that are permanent! Horrified, Mabel goes on a quest to find a cure for her brother before it's too late, but what will it take to finish what she accidentally started?
1. Prologue-Chpt3

**Hello there my lovelies! This is not my first fanfiction, however, it is my first Gravity Falls fanfiction, so I am trying to get used to the characters. Excuse some mistakes please, I'm sick right now and my spell/grammar checking gear isn't fully kicking in yet. My writing skills are a little rusty, I'm not gonna lie ^^ Thanks!**

Prologue

Wind whistled through the trees. The waterfall beat down on the pond, lilies scattering and fish flinging themselves into the spray despondently.

In the dark forest, a single swinging shape plodded along, humming to a foreign tune. In the darkest blob of shadow the figure carried a shining bottle filled with clear green liquid.

Her mouth moved; the figure giggled as she talked. Her voice was high in pitch and sounded like dolphins screeching in the ocean, happily frolicking. It had the hint of a dull-voiced, clucking chicken.

"Ah, Dipper will never guess who did this," the girl was chattering cheerfully to another dark shadow waddling beside her. "Right, Waddles?"

"Oink," came the throaty response.

"Tee hee! I wonder what this potion will do to him."

"Oink?"

"Of course I don't know what it is! Silly pig..." she stopped and sat down, panting. Pulling a water bottle from her side sweater pocket she took a long gulp. "I found it in a forest! With this vial and everything!"

She got back up, eyes glinting, and smoothed back her curly-tipped chocolate brown hair to sleek perfection.

"What'll his reaction be? If it makes him get taller like that one magical crystal growth-spurter or whatever, he'll take it! But what if it turns him into a mushroom? That would be so funny! I'll have to test it out before I use it..."

The girl went on and on to her pet, skipping happily back to the cabin through the dark forest.

Meanwhile, in the emerald green bushes, two large pairs of eyes watched. One belonged to a tall boy with piercings and long bangs, and the other belonged to a much smaller boy with angel-wing white hair that stuck up in an oval curve.

"I will have my revenge," the latter whispered in a strong accent. "Dipper Pines, I will have my revenge..."

Chapter 1

Sneaking into the Mystery Shack wasn't easy. It required amazing skill and talent.

Or, it just required a key.

Mabel slipped through the doorway, her shoulders hunching as she quietly padded to the attic.

As she passed Soos' sleeping headquarters, she was reminded of the time; actually, just a few days ago; of when her and Dipper had switched bodies.

"Heh, that was fun," she remembered with a smile. Except for being an 'awkward and smelly' boy, it was fun to sabotage Dipper's chances of getting the room.

Turning away, she crossed the dimply lit hallway, through the stairs and to the attic door. Once there she took a deep breath and glanced down at Waddles.

"Is this a good idea?" she whispered to her friend and pet.

Waddles was eating the carpet; he wasn't paying attention. She sighed and opened the door, ignoring it when it squeaked like a mouse.

She tiptoed to where Dipper was sleeping. Her brother was lying half off and half on the bed, snoring and drooling a tiny bit. His thick brown hair was messy from where his hat was usually placed and he twitched a few times as she watched. She took the liberty of cleaning his face with his pillow before she shoved him all the way back onto the bed. Her breath whistling slightly through her braces, Mabel sat down next to him and took the cap off of the lid.

Leaning over her brother, she tipped the vial. Green liquid poured from the glass, and Dipper coughed once as some dribbled too fast into his throat, but once the weird-smelling liquid was done coating her brother's throat she stepped back and lightly placed the vial on his dresser.

She briefly wondered if her twin would get so irritated by not knowing what had given him a gross taste in his mouth(or worse) that he would check for fingerprints on the vial, but Mabel pushed it away.

"He's not smart enough for that," she scoffed. Immediately feeling guilty she corrected herself. "He doesn't have the equipment."

Satisfied, she took off her sweater, got into her bed, and as soon as her head hit the pillow she heard Dipper mutter something.

"What was that?" she wondered out loud.

He said it again, and it was clearer now.

"Umph... get... away... evil... get..." he groaned and flipped onto his side.

Mabel sat up and watched her brother.

"I wonder what he's dreaming of," Mabel said with a smirk.

Dipper suddenly snapped up, jerking slightly as he sat up. He was wrapped up in his blanket.

"Ugh... Mabel...get away..." he moaned and fell backwards, fluttering awake for a moment. He then sneezed.

Mabel blinked.

"This is gonna be a long night."

She sighed and lay back down, covering her pillow with her ears as Dipper continued to groan about Wendy and Robbie and herself, Mabel , and the economy and all sorts of things only he cared about.

Chapter Two

Dawn light flooded through the breaks in the window. Dipper blinked open his eyes and yawned, pulling the covers over his face.

"Too early," he mumbled.

"How's my favorite Dipper?!" Mabel yelled outside of the blanket.

Dipper shoved her away from him, annoyed and a little shaken from her sudden entrance. "Can you pass me my hat?"

"Do you need it?" Mabel replied, but she slipped it under the blanket anyway.

After fixing it onto his head(with some difficulty), Dipper sat up straighter and wiped his hand over his forehead. "Is it hot in here or just me?"

"You're under a blanket," Mabel's voice came pointedly. He scowled at his sister and, reaching under the blanket, grabbed her hand and pulled her under the covers.

"Dipper!" she laughed, struggling to get away from him. "Hey!"

She wriggled away as he tried to get out from under the light covers. Landing with a thump, Dipper reached for Mabel to shove her over but instead of cool air greeting his hand like it should, outside of the blanket it still felt hot.

"Is it hot already? It's too early." Mabel's slightly younger twin was getting worried. Why was it so hot?

"Dipper, don't be ridiculou-" she broke off.

Dipper poked his head out from under the covers. "What?"

"AHHHHHH!" Mabel screeched, scrambling backwards. It looked like she was trying to... get away from him.

"What? What?" he panicked, throwing the blanket off of him.

"G-Get... away..." Mabel whispered, tripping over the bed frame as she turned. She landed on the soft mattress but quickly did a summersault and took off out the door and through the hallway.

"AAAAHHHHHHHHHH..." her voice was fading as it traveled away.

"Well..." Dipper said shakily. "That was... not an experience I would have liked to live."

He got up and searched around for a mirror. "There must be a reason why she was so scared of me..."

His hands grasped something cold and slick. Pulling the mirror out from under Mabel's bed, he brought it up to him.

"Ah, now we'll find out why she ran away screaming."

Half narrowing his eyes, worried about what he looked like when he saw himself in the mirror, he held it up.

"I'm probably just sick or something... that would explain the heat. Maybe I have a fever or-"

Dipper's jaw dropped. He twitched and his hand grasping the mirror opened. The reflecting film cracked as it hit the ground. Glass littered the boy's socks and he fell backward, his head hitting the bed side as he fell back.

Dark spots jumble together. Dipper's eyes closed, but not before he could make out one thought:

_It's not possible._

Chapter Three

"Grunkle Stan! Grunkle Stan!"

Mabel's great uncle turned from his game of go-fish with Soos to glare at his niece.

"What?" he grunted, his voice gritty. He took his cap off and dusted it off while Mabel got her bearings.

"Okay, Grunkle Stan. Are you listening?"

"Yes," he growled. "Hurry up."

Mabel straightened, tapping her foot on the ground impatiently.

"Okay, listen. Last night I found a potion thingy in the woods. I gave some to Dipper because I didn't want to try it first. And this morning he woke up and he fell off the bed and he stuck out his hand to push me over, except it wasn't a hand- it was a paw."

Grunkle Stan stopped dusting and Soos stopped shuffling. Both men just looked at her.

"A... paw?" asked Soos curiously.

"Yes. The potion turned him into some sort of cat/human hybrid!" Mabel cried.


	2. Chapter4

Chapter Four

"So... are you sure he was a cat, human... whatever... thing?" Soos asked as the three paraded up the stairs to the attic. It was silent, and Mabel wondered if Dipper had just decided, "screw it, I'm outta here!" and jumped out the window...

And then they heard a scream, which meant that Dipper was still there. And then they heard an, "... what happened to me?! Who..." and then some more screaming, and Stan chuckled as they made their way up the dark, cobweb-wrapped stairs.

Soos glanced over at him.

"Why are you laughing?" he asked in his gruff, dull voice.

"How different his screams sound when he's a werecat thing," Mabel's grunkle replied. She glared at him. He shrugged and mumbled, "they're deeper, not higher, jeez kid."

Finally they reached the door. Soos reached forward, flinched and drew back. When Stan made an angry 'what's up' sign with his hands, Soos whispered, "I can't see a furry Dipper! It'll ruin my image of him!"

At that moment a voice came from behind the three. "Hey, why's everyone crowded around the attic door?"

"Wendy?" they all cried, turning in unison. The teenager was standing on the last step, looking bored as ever.

"Hey," she said with a wave.

"Dipper got turned into a cat slash human thing accidentally," Mabel piped up.

Wendy just laughed.

"Alright, where's Dipper actually?"

"In the attic, turned into a cat," Soos said with a shrug.

Wendy blinked once. She stared at them. Then she raised a hand to stretch and said, "you're not joking?" She tried to believe them. She'd seen ghosts and a large amount of other creatures, but she was struggling to believe that the kid had been somehow 'magically' turned into a werecat.

"Nope," Stan said. "See for yourself."

His scarred hand reached for the knob and quickly, suddenly, the door was swung open.

The girls and men peered in. No one was there, and when they walked into the room the only thing on the floor were claw marks(from Dipper, they assumed), Dipper's hat, Waddles, dirty laundry and torn shorts.

Wendy pointed to the window, the only escape route. "It's not open, so Dipper's still here."

"And so is his hat," Soos observed.

"And his shorts," Mabel said shortly.

"Wendy?!" came a frantic voice from somewhere under Mabel's bed. Grunkle Stan was right, it did sound considerably deeper and more noticeable.

"Dipper?" Mabel asked softly before Wendy could reply.

A shaky chocolate brown paw slowly reached for the hat and disappeared as quickly as it had come.

"Was that your... um... hand slash paw thing, Dipper?" Stan asked.

Wendy and Mabel crept in first to have a look under the bed, but as soon as Mabel crouched down there was a scrambling under the bed and a mutter of something.

"What was that?" Mabel whispered, looking down under the bed.

Everyone noticed her flinch.

She could just make out Dipper's almost inaudible voice from in the dark.

"You're scared of me, aren't you."

No one tried to correct him.


	3. Chapter 5

Chapter Five

"Dipper, c'mon out of there," Mabel begged. The sun was already at its highest point at the sky and the birds were already out singing by the time Dipper responded to his sister.

"No," he muttered.

"It can't be that bad," Wendy tried for the 50th time.

"No," he said again. Stan and Soos were in the gift shop taking over Wendy's job because the girls were trying to coax Dipper out from under the bed. Mabel had even tried knocking him out(much to her displeasure) and dragging him out from under the bed, but while struggling Dipper accidentally knocked **her **out. Wendy had warned him to be more careful, and miserably Dipper had said he would.

No one had yet seen him, except for a twitching brown tail and his paw, which he had figured out to unsheathe and sheathe at will in case he wanted to score his claws some someone's shirt(he had found out by accident and was stricken to a point of not talking for two hours).

Finally Wendy shoved herself under the bed and Mabel heard her swear once as she dragged a very undignified looking Dipper out from the dark shadow.

"Let me go!" Dipper was growling, reaching for the bed with human-like furry arms.

Mabel crawled out from her space between the bed and dresser and looked Dipper up and down.

"You don't look too bad," she said cheerfully.

"You just look like a werecat," Wendy told the young lion/boy. "Actually, a werelion," she corrected. She turned him around as he glared at her, and she ran her hand through the dark fur edging his spine. He made a half purr, half growling sound and twitched his feathery tail tip.

Wendy smirked. Mabel watched her curiously.

"You like that, huh?" the red-haired teen said, raising her hand to scratch at the beginnings of a mane growing around his neck like she would a dog.

Dipper half-closed his eyes, then snapped them back open again, jumping out from between Wendy's arms and crossing the floor in one leap, landing on his bed. It sank under his weight and he carefully jumped off again, sitting down.

"Hey," he snapped angrily. "I'm not a pet!"

"Obviously, you're a lion, which isn't a pet," Mabel said.

Dipper glared at her with eyes only a shade darker than his fur. He reached up with his paw to flip his hat so a tuft of hair sprung from the back hole.

"That's better," he said.

Wendy was watching him cautiously. "You know, you'd be the biggest tourist attraction in the Mystery Shack if Stan could see you now. He could-"

Dipper raised his hackles angrily and then noticed, sitting back down again with a slightly thump, curling his tail around his paws.

"I'm not going to be put into a cage," he muttered cooly.

"No one said you'd be in a cage," Mabel told him.

She carefully reached for his shoulder and he quickly jumped to his feet, startling his sister.

"Sorry," he mumbled, seeing that he had scared her.

"No, I'm sorry. I did this to you," his twin said sadly, watching him.

Dipper blinked, eyes wide. His tail lashed, and then, again, he noticed and sat on it.

"What? You did this?"

"Oops," Wendy muttered.


	4. Chapter 6

**Hey guys.**

**Sorry for not updating. Today I took a big risk and read 'Dipper Goes to Taco Bell'.**

**I say big risk because I figured it maybe had violence or something.**

**I did it anyway.**

**And now I'm kind of turned off of GF for a while.**

**It basically ruined my image of the twins. Now I have no idea what to write.**

**I'll continue writing soon, but for now, I really need a break...**

**It just... basically ruined me -.-**

**Take my advice: don't read it.**

**Thanks,**

**Fess**


	5. Chapter612

**Hey guys! I'm back. I know, I know, after about only a day and a half... I got over it quicker than I thought.**

**I won't be working on Social Rejects for a while. I'm surprised so many people like it!**

**Thanks, Followers, Readers, Reviewers. I wouldn't continue this if I had no audience :)**

**Please R&R,**

**Fess**

Chapter Six

"You did this to me!" Stan was listening to an argument take place in the room above him. He was sweeping grumpily while Soos managed the cash register. People were coming and going, but nobody could help them because both men were busy, Dipper was a lion and Wendy and Mabel were getting yowled at above him.

He chuckled. Ah, good days.

The whole day was gone and eventually Wendy had left. Dipper was still getting used to fur and no thumbs and Mabel turned on about five dusty fans to blow on him because he was panting.

"Hey Dip," Mabel asked after a while. She was lying on her back on her bed reading a magazine about Sev'ral Times' escape, which she helped in. "Can I ride on your back like a horse?"

"No," he replied. He was trying to get his dewclaws on his forepaws to operate as opposable thumbs while reading 3.

"You know, this is stupid," Mabel suddenly spat, throwing her magazine on the ground and turning to lie on her side.

"What is?" Dipper wasn't even paying attention, trying to find a cure for his sudden lion transformation.

"I'm just... it's just... I'm sorry," she moaned. She turned back to the wall and nuzzled against Waddles.

"It's fine."

It wasn't, really, but Dipper didn't want his sister to feel guilty. It wasn't exactly her fault, anyway, it was whoever put the vial out...

"No, it's not." Dipper was surprised by the venom in her voice. "I did this to you. I should be the one to fix it."

Dipper rolled his eyes. "Don't be ridiculous, Mabe-" she cut him off by starting to cry.

"C'mon, Mabel, don't do this to me," he begged. He couldn't stand to hear his sister cry for something she had no more control over.

She wiped away tears and sat up. Her nose was running and her eyes were already red, her cheeks wet with the salty flow. She immediately felt embarrassed and shoved her face into a pillow.

"I-I'm sorry," she whispered softly into the pillow.

Dipper set his book down and crossed over to her. Brushing his paws against her hair delicately, like he was touching porcelain, the lion boy said, "at least you can still understand me, right? And I can understand you. It's all good."

"It might be permanent," Mabel sobbed.

Dipper bit his lip and then flinched as his fang pierced the tender skin.

"No," he argued. "It's fine."

He bunched his muscles and sprang up onto the bed, curling up beside her and resting his chin on her back. Obviously something he would never do if he was a human, because it would look funny, but since he was a lion, well, he had a free pass. Plus, her sweater was made of comfortable material.

As the afternoon went on to evening, Mabel's sobs quieted to sudden jerky movements and then faded until she was sleeping soundly. Dipper fell asleep curled up by his sister, and when Wendy went in to check on them she left a macaroni dinner by Mabel and some steak for Dipper.


	6. Gideon- Chpt 7 and 8

Chapter 7

**WOAH.**

**WOAH.**

**WOAH.**

**WOAH.**

**(Okay I'm done now)**

**MOAR.**

**It's apparently not on hiatus...**

**so...**

**here :3**

**I've also combined two short chapters into one, so here you go:**

Birds chirped. Bugs hummed, buzzing around his ears. The dark brown rings twitched and flicked back.

Dipper's eyes opened up slowly. He blinked the sleep murk out of them and yawned, stretching.

The bed springs groaned. Dipper snapped alert, awake. If the bed collapsed, with Mabel on it... oops.

He jumped off and landed awkward, twisting and succeeding in spraining his paw. Yelping in pain, he staggered backwards and slipped on the steak, which slid in front of him as he fell back.

Mabel's head shot up.

"Dip? Are you okay?"

"No," he snapped, getting off the ground and shaking his paws to get the steak blood off of them.

Mabel sighed. "I need to go talk to Gideon."

Dipper stopped and glared at her, rigid.

"No! You can't! He tried to kill me, remember?"

"I don't have a choice," she replied. The 12-year-old leaped off her bed and fumbled around in her suitcase for a fresh sweater. "He might know a cure to the potion."

"If you ask me, I'm sure he **created** the potion," Dipper mumbled under his breath. Lifting his paw to his hat he flipped it back to his usual angle.

"Don't be silly," Mabel scoffed, but her heart jumped into her throat, squeezing it tight. "That's ridiculous."

Chapter 8

Mabel crept up alongside the chipped paint of the right wall. She could easily see Gideon's figure stalking(or pacing, more accurately) in his room.

Mabel took a deep breath and rapped on the door twice.

Gideon's father opened the door and looked surprised to see her.

"Mabel, dear, what ever are you doing here at this hour?"

Mabel heaved a deep sigh. "Sorry, Mr. Gleeful. I need to speak with Gideon."

Bud chuckled. "Alright, hun. You know where his room is?"

"I can guess," she admitted. "The attic."

A girl with long, curly brown hair and dark mocha eyes stood in the dark doorway of Gideon Gleeful.

"Gideon," she admitted with a deep sigh. "I need your help."


End file.
